1. Field of the Invention
The present invention relates to track systems for tracked vehicles, and, more particularly, to a rubber track having metal internal links.
2. Description of the Related Art
Farmers utilize a wide variety of vehicles and implements, among them are vehicle having tracked drive systems. A tracked drive is a system of vehicle propulsion in which a continuous band of treads is driven by two or more wheels. This band is typically made of modular steel plates, in the case of military vehicles and construction equipment, or rubber reinforced with steel wires in the case of agricultural or lighter construction vehicles. The large surface area of the track distributes the weight of the vehicle better than wheels on an equivalent vehicle, enabling a continuous tracked vehicle to traverse soft ground with superior traction and less likelihood of becoming stuck. An advantage of the use of metal plates is that they are both hard-wearing and damage resistant, especially in comparison to rubber tires. The aggressive nature of the track provides good traction in soft surfaces, but can damage paved surfaces. Special tracks can be configured to allow the installation of rubber pads on the treads for use on paved surfaces to prevent the damage.
Tracks are typically built from modular links, which are linked together to form a closed chain. The links are joined by a hinge like pivotal coupling, which allows the track to be flexible and wrap around a set of wheels to make an endless loop. The links are typically broad, and made of a manganese alloy steel for high strength, hardness, and abrasion resistance.
Generally, track construction and assembly are dictated by the application. For military vehicles often a track shoe that is integral to the structure is used in order to reduce track weight. In contrast, agricultural and construction vehicles often use a track with shoes that attach to the chain with bolts and do not form part of the chain's structure. This allows track shoes to break without compromising the ability of the vehicle to move and decrease productivity but increases the overall weight of the track and vehicle.
There can exist some general disadvantages of tracks, which may include a lower top speed, much greater mechanical complexity, shorter life and damage that the all-steel versions cause to what they travel over. In an urban environment vehicle laws and local ordinances often require rubberized tracks or track pads be used on tracked vehicles. A compromise between all-steel and all-rubber tracks exists: attaching rubber pads to individual track links to ensure that the tracked vehicles can travel more smoothly, quickly, and quietly on paved surfaces. While these pads may reduce a vehicle's traction, they reduce damage to pavement.
Many vehicle manufacturers provide rubber tracks instead of steel, especially for agricultural applications. Rather than a track made of linked steel plates, a reinforced rubber belt with chevron treads is used. In comparison to steel tracks, rubber tracks are lighter, make less noise, create less maximal ground pressure and do not damage paved roads. The disadvantage is that they are not as solid as steel tracks.
Generally rubber tracks are formed around a basic carcass or belt. The carcass includes an endless belt-shaped rubber-like elastic member, a number of core bars, which can be made of metal, can be embedded therein and aligned and extend in traverse direction of the track. Steel cords, which serve as tension-resistant members may be embedded in the endless elastic member to surround the core bars.
A concern about the expense of a metal linked track is the cost of the castings or forgings needed to build each link. Concerns about rubber tracks are the durability and traction.
What is needed in the art is a track system that has less expensive metal links and improved traction.